This invention relates to methods of and/or means for indicating the levels of liquids and has been devised particularly though not solely for use in measuring the level of milk in a vessel.
It is an object of the present invention to provide methods of and means for measuring the level of liquid in a vessel which will at least provide the public with a useful choice.
Accordingly in one aspect the invention consists in a method of indicating the level of an electrically conducting liquid in a vessel, said method comprising the steps of allowing the liquid to rise in the vessel which contains a vertically disposed rod type resistor having an average cross sectional dimension between twenty and forty five mm and a resistance of between three and thirty two ohms per mm of length of the resistor, said method comprising the steps of allowing the liquid to rise in the vessel in a manner such that the liquid interconnects adjacent lengths of the resistor thus changing the impedance of the resistor appearing at the terminals thereof, measuring that change of impedance and converting the change of impedance into a display which indicates change of level in liquid in the vessel.
In a further aspect the invention consists in apparatus for indicating the level of an electrically conducting liquid in a vessel said apparatus comprising a rod type resistor disposed vertically in use in said vessel, said resistor having an average cross sectional dimension between twenty and forty five mm, and a resistance of between three and thirty-two ohms per mm of length of the resistor and being arranged so that increase in the level of liquid in the vessel causes some of the liquid in the vessel to interconnect adjacent lengths of the resistance wire to change the impedance thereof, means for measuring such change in impedance and display means on which change in level of liquid in the vessel is indicated.
To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.